The ranger lodge on the capital world is a total waste and gets replaced ASAP, and I never bother building lodges on planets with less than two pre-existing natural blockers as I have rather arbitrarily decided that 6 base unity for 2 energy and a building slot is my Environmentalist pain threshold. The ranger jobs are essentially sociologist clerks, and useful in the same situations as clerks are useful for non-trade based empires, i.e. very rarely.
That said, I like Environmentalist as a 2nd civic for planned wide high-unity games, but it can be a bit hit-and miss.
Sometimes you get unlucky and the first planets just have one or two natural blockers, or perhaps none at all, and nothing you can get your hands on in the early game has a significant number of natural blockers, in which case all you have to fall back on is the -20% CG and that just isn't quite enough to make up for the opportunity cost.
But mostly you'll get a few 2-4 blocker planets where the extra POP-free unity from that is so very sweet and comes in helpful not only in the very early game, but for quite some time into the midgame if you haven't already swapped it out on the 3rd civic swap.
And then there are games when you realize that it is 2231, and you haven't reformed for 3rd civic yet because you really don't want to get rid of environmentalist as originally planned, and consider reforming to get a 3rd while keeping it instead as is the case in my current game.
12 ranger lodges, 24 energy upkeep. 155 unity. I'm loving it. (Natural blockers 1x6, 3x4, 4x3, 4x2 excluding preserves.)
Anyhow, the Composer of Strands loves it, which is as good an excuse as any for keeping it around.
(Though admittedly the Environmentalist civic isn't the reason this particular game ran off the rails and will probably soon be abandoned. Getting an Avatar on my second Shroud visit and cowing all the nearby AIs into submission is to blame for that.)
Also, a fringe benefit of playing with Environmentalist is that it indirectly trains you to be a better player.
Hear me out!
One of the more subtle wastes of energy in Stellaris is clearing blockers before you strictly need to. Sure, sometimes you need to do it to ensure maximum growth on 10+ POP planets or to free up districts, but more often thoughtful use of districts in the first place means that this can be put off until the midgame or later and the energy invested in other things for all but a few planets - and the Environmentalist civic is the perfect civic for constantly reminding the player of that better playstyle.